All of this re-inforces my opinion that autonomous vehicles have no place on the highway and should only be used on Special Roads, where traffic is restricted, regulated, controlled, streamed, with unexpected happenings minimised*. The problem is that most of the development research on auto-vecs is in the US where they don't have the legal concept of Special Roads, so they are being bogged down with trying to cope with being on the public highway.
*I have a strong memory of some early scifi having a throw-away sentence along the lines of: he pulled out onto the motorway, put the car in automatic, dropped the seat back and began to snooze. This is *exactly* the environment auto-vecs are suitable for.